Bafang error 15: Motor temperature sensor error
Bafang BBS01/BBS02/BBSHD, M-series mid-drives and hub motors (UART & CAN displays)Dealer neededRide with caution
The controller cannot read the motor's temperature sensor: open circuit, short, or an implausible value. Some firmware only warns, others limit power. The motor itself may still be fine, but the protection is gone.
Likely causes
- Broken sensor wire in the motor cable or connector
- Corrosion on the temperature pin of the motor plug
- Failed sensor inside the motor
- Motor without a temperature sensor used with a controller that expects one (after a motor swap)
How to fix Bafang error 15
- Unplug the motor connector, clean and dry it, and re-seat it
- Check the motor cable for damage, especially near the axle
- If the motor was recently replaced, confirm the new motor has a temperature sensor
- Have the sensor replaced inside the motor or replace the motor cable
Go to a dealer if: Go to a shop if the connector is clean; the sensor is inside the motor and needs opening it.
Warranty: If the bike or kit is under warranty (usually 1-2 years via the seller), contact them before opening anything, as opened motors and controllers can void the claim.
Typical cost: Motor cable EUR/USD 30-60; opening the motor to replace the sensor EUR/USD 80-150 in labour.
Warranty: If the bike or kit is under warranty (usually 1-2 years via the seller), contact them before opening anything, as opened motors and controllers can void the claim.
Typical cost: Motor cable EUR/USD 30-60; opening the motor to replace the sensor EUR/USD 80-150 in labour.
Still stuck? Take a photo of the display and show it to a local e-bike workshop. Bring the bike's system name (e.g. Bosch Performance Line CX) and the exact code; that saves diagnostic time and money.
Frequently asked
Can I reset error 15?
Only if the cause was a dirty connector. A broken sensor trips it every start.
Can I keep riding?
Usually yes at reduced assist, but watch the motor temperature by hand on long climbs.
Warranty?
Yes within the motor's warranty; a crushed cable is not covered.
Related Bafang codes
Not an official Bafang document. Compiled from workshop experience and public service information; details can differ per system version and bike brand.